51645469 has 2 divisors, whose sum is σ = 51645470. Its totient is φ = 51645468.

The previous prime is 51645431. The next prime is 51645493. The reversal of 51645469 is 96454615.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50765625 + 879844 = 7125^2 + 938^2 .

It is a cyclic number.

It is not a de Polignac number, because 51645469 - 2²⁵ = 18091037 is a prime.

It is a super-2 number, since 2×51645469² = 5334508936459922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51645499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25822734 + 25822735.

It is an arithmetic number, because the mean of its divisors is an integer number (25822735).

Almost surely, 2^51645469 is an apocalyptic number.

It is an amenable number.

51645469 is a deficient number, since it is larger than the sum of its proper divisors (1).

51645469 is an equidigital number, since it uses as much as digits as its factorization.

51645469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 40.

The square root of 51645469 is about 7186.4782056303. The cubic root of 51645469 is about 372.4009171479.

The spelling of 51645469 in words is "fifty-one million, six hundred forty-five thousand, four hundred sixty-nine".